Heat-fusion composition and multi-layer molded body containing layer comprising the same

ABSTRACT

The present invention provides a heat-fusion composition for molding into multi-layers containing a block copolymer (a) having epoxy groups, wherein the heat-fusion composition for molding into multi-layers further comprises 20 to 80% by weight of a block copolymer (a) having epoxy groups and 20 to 80% by weight of at least one kind of thermoplastic elastomer (b) selected from styrene elastomer, polyurethane elastomer, polyester elastomer, polyamide elastomer, polyolefin elastomer and polyvinyl chloride elastomer (with a combined content of (a) and (b) of 100% by weight) along with the block copolymer (a) having epoxy groups and thermoplastic elastomer (b). A multi-layer molded body according to the present invention being excellent in the heat-fusion property can be obtained by allowing the heat-fusion composition for forming into multi-layers to heat-fuse with a hard resin. The molded bodies obtained can be used for a turn table of a CD-ROM driver, a side braid of the door of a car, clips and handles of the electric appliances, spacers, packings, air bag covers, push buttons of the key board of a personal computer, sound damping gear and sports shoes sole and so on.

TECHNICAL FIELD

The present invention relates to a heat-fusion composition for use in amulti-layer molding (referred to a heat-fusion composition hereinafter)and a multi-layer molded body obtained by a double injection molding, aninsert molding, a multi-layer extrusion or multi-layer blow molding of aheat-fusion composition and a hard resin. In more detail, the presentinvention relates to a multi-layer molded body containing a layercomprising a heat-fusion composition composed of a block copolymerhaving epoxy groups and a thermoplastic elastomer.

BACKGROUND ART

Hard resins and thermoplastic elastomers have been molded into amulti-layers in the conventional art. This multi-layer molding makes useof the function of elastomers such as soft feeling and slip preventiveproperty as a surface skin material, along with integrating theelastomer into a seal material and packing material to obtain a moldedbody with a good water-proof property. Integrated molding can also savethe cost for adhering the hard resin with the thermoplastic resin. Manymolded bodies and heat-fusion compositions have been recently proposedthrough the attempt to improve the fusion property of the hard resinsand thermoplastic elastomers.

Japanese Examined Patent Publication No. 4-2412 proposes a multi-layerinjection molded body comprising (a) an elastomer of a hydrogenatedblock copolymer obtained by hydrogenating a block copolymer comprising apolymer block A mainly composed of at least two vinyl aromatic compoundsand a polymer block B mainly composed of at least one conjugated dienecompound and (b) a resin selected from a polyolefin resin, polystyreneresin and ABS resin. However, the elastomer of hydrogenated blockcopolymers used in the invention cited herein has no functional groupsto enhance the adhesive property, imposing a limitation in theheat-fusion property.

Japanese Unexamined Patent Publications No. 1-139240, No. 1-139241, No.3-100045, No. 6-65467 and No. 6-107898 propose a method for producing acomposite molded body comprising a thermoplastic elastomer composition,in which a styrene-based thermoplastic elastomer having no functionalgroups is combined with other thermoplastic elastomers, and a hard resinselected from polycarbonate, nylon 11, nylon 12, ABS resin and PMMAresin.

However, the styrene-based thermoplastic elastomers used in theinvention cited herein has no functional groups to enhance the adhesiveproperty, rendering the compositions poor adhesive property.

Japanese Unexamined Patent Publication No. 8-59954 proposes acomposition in which (a) a hydrogenated block copolymer obtained byhydrogenating a block copolymer comprising a polymer block A mainlycomposed of at least. one vinyl aromatic compound and a polymer block Bmainly composed of at least one conjugated diene compound, and/or amodified hydrogenated elastomer in which the hydrogenated blockcopolymer is bound with a molecular unit containing a carboxylic acidgroup or its derivative group, (b) a polystyrene based resin and/or apolyphenylene based polymer and (c) a thermoplastic elastomer comprisingan ethylene—unsaturated carboxylic acid ester copolymer are laminated ona resin mainly composed of the resin (b). Although the heat-fusionproperty of the modified hydrogenated block copolymer as used herein hasbeen improved by virtue of functional groups since the resin is modifiedwith a carboxylic acid group or its derivative group, the resin is onlyable to fuse with so-called modified PPO resins. Accordingly,developments of a heat-fusion resin being able to fuse with an widerrange of resins are desired.

The object of the present invention is to provide a heat-fusioncomposition that contains a block copolymer having epoxy groups and hasa heat-fusion property with a hard resin, and a multi-layer molded bodyin which the layer comprising the heat-fusion composition and a layercomprising various kind of hard resins are strongly heat-fused.

DISCLOSURE OF INVENTION

For the purpose of solving the problems as hitherto described, theinventors of the present invention have extensively and preciselyinvestigated the epoxydized block copolymer compositions having epoxygroups as functional group, finding that an excellent multi-layer moldedbody can be obtained by taking advantage of heat-fusion properties of acomposition containing a block copolymer having epoxy groups, especiallya composition comprising a block copolymer having epoxy groups and aspecified thermoplastic elastomer, thereby completing the presentinvention.

The first embodiment according to the present invention provides aheat-fusion composition containing a block copolymer having epoxy groupsand a heat-fusion composition comprising a block copolymer having epoxygroups and a thermoplastic elastomer.

The present invention also provides a heat-fusion composition comprising(a) a block copolymer having epoxy groups, for example an epoxydizedblock copolymer obtained by epoxydizing a block copolymer comprising apolymer block mainly composed of a vinyl aromatic hydrocarbon compoundand a polymer block mainly composed of a conjugated diene compound, orits hydrogenated product and (b) at least one kind of thermoplasticelastomer selected from a styrene elastomer, polyurethane elastomer,polyester elastomer, polyamide elastomer, polyolefin elastomer andpolyvinyl chloride elastomer, wherein the blending ratio of thecomponent (a) is in the range of 20 to 80% by weight and the blendingratio of the component (b) is in the range of 20 to 80% by weight with acombined amount of (a) and (b) of 100%. The present invention alsoprovides a heat-fusion composition containing (d) 0.01 to 25 parts byweight of a polyfunctional compound containing at least two functionalgroups reactive to the epoxy group in the molecule and/or (e) 0.001 to 2parts by weight of an accelerating agent for the curing reaction ofepoxy groups per 100 parts by weight of the heat-fusion composition. Thepresent invention further provides a heat-fusion composition comprising(c) 10 to 50 parts by weight of a hard resin and (d) 0.01 to 25 parts byweight of a polyfunctional compound containing at least two functionalgroups reactive to the epoxy group in the molecule and/or (e) 0.001 to 2parts by weight of an accelerating agent for the curing reaction ofepoxy groups per 100 parts by weight of the heat-fusion composition.

The second embodiment according to the present invention provides amulti-layer molded body composed of a layer comprising the heat-fusioncomposition according to the first embodiment and the other layer, forexample a layer comprising at least one kind of resin selected from anABS resin, impact resistant polystyrene, polycarbonate,polytmethylmethacrylate, polypropylene, saturated polyester resin,polyamide, polyvinyl chloride and polyphenylene oxide resin. The presentinvention also provides a multi-layer molded body composed of a layercomprising the heat-fusion composition according to the first embodimentand a layer comprising a composition prepared by blending (d) 0.01 to 25parts by weight of a polyfunctional compound containing at least twofunctional groups reactive to the epoxy group in a molecule, for examplea polyfunctional compound containing at least two different or identicalfunctional groups selected from an amino group, a carboxylic anhydridegroup, a phenolic hydroxide group, a hydroxyl group and a carboxyl groupin a molecule, and/or (e) 0.001 to 2 parts by weight of an acceleratingagent for the curing reaction of epoxy groups per 100 parts by weight ofthe hard resin of the other layer.

BEST MODE FOR CARRYING OUT THE INVENTION

The present invention will now be described in more detail hereinafter.The heat-fusion composition according to the present invention ischaracterized by containing a block copolymer (a) having epoxy groups.The heat-fusion composition according to the present invention alsocomprises a block copolymer (a) having epoxy groups and a thermoplasticelastomer. The heat-fusion composition according to the presentinvention further comprises a block copolymer (a) having epoxy groups,for example, an epoxydized block copolymer obtained by epoxydizing ablock copolymer comprising a polymer block mainly composed of a vinylaromatic hydrocarbon compound and a polymer block mainly composed of aconjugated diene compound or a hydrogenation product of the foregoingpolymer block, and a thermoplastic elastomer (b), for example at leastone kind of elastomer selected from styrene elastomers, polyurethaneelastomers, polyester elastomers, polyamide elastomers, polyolefinelastomers and polyvinyl chloride elastomers.

The heat-fusion composition according to the present invention has agood heat-fusion property with a hard resin, forming the multi-layermolded body composed of a layer comprising the heat-fusion compositionand a layer comprising the hard resin into a strongly heat-adheredmolded body with each other.

Vinyl aromatic compounds as one component of the polymer blockconstituting the block copolymer (a) having epoxy groups can beselected, for example, from at least one of the compounds comprisingstyrene, a-methylstyrene, vinyltoluene, p-tert-butylstyrene,divinylbenzene, p-methylstyrene and 1,1-diphenylstyrene. Styreneispreferable among them.

Conjugated diene compounds as components of the other polymer blockconstituting the block copolymer (a) can be selected, for example, fromat least one of the compounds comprising butadiene, isoprene,1,3-pentadiene, 2,3-dimethyl-1,3-butadiene, 3-butyl-1,3-octadiene andphenyl-1,3-butadiene. Butadiene and isoprene, and a combination thereofare preferable among them. The block copolymer as used herein refers toa block copolymer comprising a polymer block A mainly composed of avinyl aromatic compound and a polymer block B mainly composed of aconjugated diene compound. A weight ratio of copolymerization betweenthe vinyl aromatic compound and conjugated diene compound is in therange of 5/95 to 70/30, the range of 10/90 to 60/40 being preferable.

The number average molecular weight of the block copolymer to be used inthe present invention is in the range of 5,000 to 600,000, preferably inthe range of 10,000 to 500,000, and the molecular weight distribution(the ratio (Mw/Mn) between the weight average molecular weight (Mw) andnumber average molecular weight (Mn)) is 10 or less. The block copolymermay have a linear, branched or radial molecular structure, or acombination thereof. For example, the block copolymer is represented bya block copolymer of a vinyl aromatic compound and conjugated dienecompound having a structure such as A-B-A, B-A-B-A, (A-B-)₄ Si orA-B-A-B-A. The unsaturated bonds in the conjugated diene of the blockcopolymer may be partially hydrogenated.

Any production methods can be adopted as the methods for producing theblock copolymer to be used in the present invention, provided that thecopolymer obtained has the structure as described above. For example, ablock copolymer of a vinyl aromatic compound and conjugated dienecompound can be synthesized in an inert solvent using a lithium catalystor the like in accordance with the methods disclosed in JapaneseExamined Patent Publications No. 40-23798, No. 47-3252, No. 48-2423, No.46-32415, No. 49-36957, No. 43-17979and No 56-28925, Japanese PatentApplication No. 49-105970 and No. 50-27094, and Japanese UnexaminedPatent Publication No. 59-166518. According to the method disclosed inJapanese Examined Patent Publications No. 42-8704 and No. 43-6636, or inJapanese Unexamined Patent Publication No. 59-133203, the partiallyhydrogenated block copolymers to be used in the present invention can besynthesized by a hydrogenation in an inert solvent in the presence of ahydrogenation catalyst. The epoxydized block copolymers to be used inthe present invention are obtained by epoxydizing the foregoing blockcopolymers in the present invention.

The epoxydized block copolymer (otherwise, referred to a epoxy-modifiedblock copolymer) in the present invention can be obtained by allowingthe foregoing block copolymer to react with an epoxydizing agent such ashydroperoxides or peroxy acids in an inert solvent. Examples of theperoxy acids include performic acid, peracetic acid or perbenzoic acid,a catalytic effect being able to obtain by using either one of theseperoxy acids or a mixture thereof together with hydrogen peroxide, or byusing an organic acid together with hydrogen peroxide, or by usingmolybdenum hexacarbonyl together with tert-butyl hydroperoxide. Theoptimum amount of the epoxydizing agent can be determined depending onvariables such as the kind of respective epoxydizing agent to be used,the required degree of epoxydation and the kind of respective blockcopolymer to be used.

The epoxydized block copolymer obtained can be isolated by anappropriate method, for example by precipitating in a poor solvent, byevaporating the solvent off after introducing the polymer into hot waterwith stirring, or by directly removing the solvent.

The degree of epoxydation is determined, after titrating with 0.1 Nhydrobromic acid, by the following equation:

Epoxy equivalent=(10.000×W)/(V×f)

wherein W, V and f denote the weight (g) of the epoxydized blockcopolymer, the titration volume with hydrobromic acid and the factor ofthe hydrobromic acid solution, respectively. The smaller the calculatedvalue is, the higher the degree of epoxydation.

The epoxy equivalent of the epoxydized block copolymer according to thepresent invention is 140 to 10,000, the equivalent of 200 to 6,000 beingespecially preferable. It is not preferable that the degree ofepoxydation is too high since a gelation product is formed duringprocessing of the heat-fusion composition obtained to result in a poorappearance while, when the degree of epoxydation is too low, heat-fusionof the composition ascribed to epoxy groups can not be expected.

The thermoplastic elastomer to be used in the constituent (b) of theheat-fusion composition will be described hereinafter. Known styreneelastomers such as styrene-butadiene block polymers (abbreviated as SBS)styrene-isoprene block polymers (abbreviated as SIS), hydrogenated SBSblock polymers (abbreviated as SEBS), hydrogenated SIS block polymers(abbreviated as SEPS) and styrene-olefin block polymers (abbreviated asSEBC) may be used for the styrene elastomers.

Examples of the polyurethane elastomers as a constituent (b) known inthe art are obtained by allowing a diol polymer (for example, polyetherbased diols such as polyalkylene glycol and polyester based diols suchas polycaprolactone) with a molecular weight of 500 to 5,000 having anactive hydrogen at its terminal to react with a low molecular weightglycol (such as ethyleneglycol) having a molecular weight of 500 or lessor with a diisocyanate (such as phenylenediisocyanate).

An example of the polyester elastomers is a block copolymer having acrystalline aromatic polyester (such as polybutylene terephthalate) as ahard segment and an aliphatic polyether (such as polytetramethyleneglycol) or an aliphatic polyester (such as polycaprolactone) as a softsegment.

An example of the polyamide elastomers is a block copolymer containing acrystalline aliphatic polyamide (such as nylon 6, 11 or 12) as a hardsegment and a polyoxyalkylene ether (such as polyethylene glycol,polypropylene glycol or polytetramethylene glycol) or an aliphaticpolyester (such as polycaprolactone), both being amorphous and having alow glass transition point, as a soft segment. The polyamide elastomersare classified into two categories of polyether ester block amides andpolyether block amides.

A polyolefin such as polyethylene or polypropylene as a hard segment isblended with an ethylene-propylene rubber as a soft segment in thepolyolefin elastomer. The method for producing the same includes asimple blending method, a dynamic cross-linking method of the softsegment, and a method for producing the same in a polymerizationreaction vessel. polyolefin copolymers are included in the polyolefinelastomers; for example polyolefin copolymers known in the art such aschlorinated polyethylene containing 20 to 40% by weight of chlorine,ethylene-ethylacrylate containing 10 to 40% by weight of ethyl acrylate,ethylene-methyl methacrylate containing 10 to 40% by weight of methylmethacrylate, carbon monoxide containing ethylene-n-butyl acrylatecopolymer containing 5 to 20% by weight of carbon monoxide and 20 to 50%by weight of n-butyl acrylate, ethylene based ionic cross-link resinknown as ionomers or ethylene-vinyl acetate copolymer containing 10 to40% by weight of vinyl acetate.

Polyvinyl chloride elastomers include a high molecular weight polymerhaving a degree of polymerization of 2,000 or more in which molecularchains are made to highly interlocked with each other, or an elastomerknown in the art having a cross-linked structure or branched structureowing to polyfunctional monomers. Polyvinyl chloride elastomers beingmade soft with a plasticizer or having a nitrile-butadinene rubber as asoft segment is also included in this category.

It is preferable that the blending ratio of the epoxydized blockcopolymer (a) and the thermoplastic elastomer (b) as constituents of theheat-fusion composition according to the present invention are both inthe ranges of 20 to 80% by weight (the combined content of (a) and (b)being 100% by weight).

The other embodiment of the present invention includes a heat-fusioncomposition prepared by blending 10 to 50 parts by weight, preferably 20to 40 parts by weight, of the hard resin (c) to 100 parts by weight ofthe heat-fusion composition. Blending the hard resin (c) allows thesurface hardness of the heat-fusion composition to be increased, ifnecessary. When the content of the hard resin (c) is less than 10 partsby weight, there is no effect for improving the surface hardness while,when the value is more than 50 parts by weight, the surface hardnessbecomes too high while decreasing the heat-fusion property.

Commonly used hard resins as well as an alloy or blend thereof areavailable for the hard resin as a constituent (c). Engineering plasticsknown in the art, such as polyphenylene ether, polyacetal, polyallylate,liquid crystal polymer, polysulfone, polyethersulfone and polyphenylenesulfide, may be used. Heat curing resins such as epoxy resins,diallylphthalate resins, phenol resins, melamine resins, urea resins andunsaturated polyester resins can be also used, provided that the resinsare limited to those being molded into a multi-layer molded body by aninsert injection molding as will be described hereinafter. However, atleast one kind of the thermoplastic resin selected from an ABS resin,impact resistant polystyrene, polycarbonate, polymethylmethacrylate,polypropylene, saturated polyester resin, polyamide, polyvinyl chlorideand polyphenylene oxide resin is especially preferable.

The well known ABS resin to be used in the present invention includesstyrene-acrylonitrile copolymers modified with a variety of rubbers suchas butadiene rubber, styrene-butadiene copolymer, ethylene-propylenecopolymer and ethylene-propylene-diene copolymer. Although ABS resinsare usually produced by emulsion polymerization or continuous bulkpolymerization, the ABS resin whose rubber concentration is adjustedwith a styrene-acryronitrile copolymer is also an well known ABS resinthat may be included in the present invention.

Examples of the impact resistant polystyrene are the highly impactresistant polystyrene modified with a variety of rubbers such asbutadiene rubber, styrene-butadiene copolymer, ethylene-propylenecopolymer and ethylene-propylene-diene copolymer.

Though carbonate resins include 4,4-dihydroxydiphenyl-2,2-propane(common name: bisphenol A) as well as 4,4′-dihydroxyallylalkanepolycarbonate, a polycarbonate of 4,4′-dihydroxydiphenyl-2,2-propanewith a number average molecular weight of 15,000 to 80,000 is especiallypreferable among them. These polycarbonate resins can be produced by anymethods. Examples of the method for producing a polycarbonate using4,4′-dihydroxydiphenyl-2,2-propane as a starting material includes amethod in which phosgene gas is blown into4,4′-dihydroxydiphenyl-2,2-propane in the presence of an alkalineaqueous solution and a solvent, or an ester exchange method of4,4′-dihydroxydiphenyl-2,2-propane carbonate diester in the presence ofa catalyst.

Examples of polymethylmethacrylate include methyl methacrylate polymer,a copolymer of methyl methacrylate with a small amount of methylacrylate or butyl acrylate and a copolymer of 20 to 80% by weight ofmethyl methacrylate with 20 to 80% by weight of styrene.

Polypropylene means a crystalline polypropylene, including, other than apolymer of propylene alone, block or random copolymers in whichpropylene is co-polymerized with, for example, a-olefin such as ethyleneand butene-1.

The saturated polyester resin is composed of a dicarboxylic acidcomponent at least 40 mole % of which is terephthalic acid, and a diolcomponent. The dicarboxylic acid components other than terephthalic aciddescribed above include aliphatic dicarboxylic acids with a carbonnumber of 2 to 20 such as adipic acid, sebacic acid and dodecanedicarboxylic acid, aromatic dicarboxylic acids such as isophthalic acidand naphthalene dicarboxylic acid, or alicyclic dicarboxylic acids suchas cyclohexane dicarboxylic acid, being used alone or as a mixturethereof. The diol components described above include aliphatic glycolssuch as ethyleneglycol, 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol,1,10-decanediol and 1,4-cyclohexanediol, or alicyclic diols, being usedalone or as a mixture thereof. The especially desirable effect of thepresent invention can be displayed when the resin is polybutyleneterephthalate or polyethylene terephthalate. The resin should preferablyhave a intrinsic viscosity in the range of 0.5 to 3.0 dl/g as measuredin a solvent of o-chlorophenol at 25° C., obtaining a high mechanicalstrength when a polyester resin with a viscosity of this range is used.

The polyamides used in the present invention include aliphatic polyamideresins such as nylon 6, nylon 6.6, nylon 6.10, nylon 6.12, nylon 11,nylon 12 and nylon 4.6, or aromatic polyamide resins such aspolyhexamethylenediamine terephthalamide, polyhexamethylenediamineisophthalamide and xylene containing polyamide, and a modified compoundor a mixture thereof. The especially preferable polyamide resin is nylon6 or nylon 6.6.

Polyvinyl chloride to be used in the present invention is a polymerknown in the art with a degree of polymerization of 700 to 1,600 inwhich additives such as an impact resistance improving agent,plasticizer, heat stabilizing agent and lubricant may be included.

A polyphenylene ether resin is a polymer obtained by an oxidativepolymerization of phenolic compounds with oxygen or oxygen containinggas using a coupling catalyst. Examples of them include phenol, o-, m-or p-cresol, 2,6-, 2,5-, 2,4- or 3,5-dimethylphenol,2-methyl-6-phenylphenol, 2,6-diphenylphenol, 2-methyl-6-ethylphenol, and2,3,5-, 2,3,6- and 2,4,6-trimethylphenol. Two or more kinds of thesephenolic compounds may be used. While the polyphenylene ether resin isused by being modified with styrene resins (such as the foregoing highlyimpact resistant polystyrene) as known in the art, these modifiedpolyphenylene ether resins are also included in the present invention.

According to the other embodiment of the present invention, aheat-fusion composition having much higher heat-fusion property ascribedto a reaction with epoxy groups contained in the epoxydized blockcopolymer (a) can be obtained by allowing 0.01 to 25 parts by weight ofa polyfunctional compound (d), containing at least two functional groupsreactive to epoxy groups in the molecule, to be contained in 100 partsby weight of the heat-fusion composition containing the block copolymer(a) having epoxy groups or in 100 parts by weight of the heat-fusioncomposition comprising (a) and thermoplastic elastomer (b). At least twofunctional groups contained in this polyfunctional compound (d) may bethe same or different with each other. The molecular weight of thepolyfunctional compound (d) is not specifically limited but a polymercompound having a weight average molecular weight of about 1,000,000 to2,000,000 is typically included in the present invention. Although theblending ratio of the polyfunctional compound (d) should be adjusteddepending on the reactivity to epoxy groups in the present invention,the ratio is 0.01 to 25 parts by weight, preferably in the range of 0.1to 20 parts by weight, per 100 parts by weight of the heat-fusioncomposition to be molded into a multi-layers. It is not preferable thatthe blending ratio of the polyfunctional compound (d) is either lessthan 0.01 parts by weight or more than 25, since the effect ofimprovement of the heat-fusion property is not sufficiently displayed inthe former case while an excessive epoxydation reaction will take placeto induce gelation in the latter case.

According to the different embodiment of the present invention, 0.001 to2 parts by weight of the accelerating agent (e) for the curing reactionof epoxy groups may be contained instead of 0.01 to 25 parts by weightof the component (d), or 0.001 to 2 parts by weight of the component (e)may be contained together with 0.01 to 25 parts by weight of thecomponent (d) in the heat-fusion composition comprising the components(a) and (d) or in the heat-fusion composition comprising (a), (b) and(d) as described above. The amount of addition of the accelerating agent(e) for the curing reaction of epoxy groups is 0.001 to 2 parts byweight and more preferably 0.01 to 1 parts by weight, the amount of 0.01to 0.5 parts by weight being especially preferable. The amount of morethan 2 parts by weight is not preferable since the curing reaction ofepoxy groups excessively proceeds to result in a gel formation.

According to the different embodiment of the present invention, theheat-fusion composition having a higher heat-fusion property can beobtained owing to a reaction with epoxy groups contained in theepoxydized block copolymer (a) by allowing 10 to 50 parts by weight ofthe component (c) and 0.01 to 25 parts by weight of the polyfunctionalcompound (d) containing at least two functional groups reactive to epoxygroups to be contained in 100 parts by weight of the heat-fusioncomposition containing the component (a) or in 100 parts by weight ofthe heat-fusion composition comprising the components (a) and (b). Atleast two functional groups contained in this polyfunctional compound(d) may be the same or different with each other. The molecular weightof the polyfunctional compound (d) is not specifically limited but apolymer compound with a weight average molecular weight of about1,000,000 to 2,000,000 may be included in the present invention.Although the blending ratio of the polyfunctional compound (d) should beadjusted depending on the reactivity to epoxy groups, the content is0.01 to 25 parts by weight per 100 parts by weight of the heat-fusioncomposition for molding into a multi-layers, the range of 0.1 to 20parts by weight being especially preferable.

It is not preferable that the blending ratio of the polyfunctionalcompound (d) is either less than 0.01 parts by weight or more than 25parts by weight, since the effect of improvement of the heat-fusionproperty is not sufficiently displayed in the former case while anexcessive epoxydation reaction will take place to induce gelation in thelatter case.

According to the different embodiment of the present invention, 0.001 to2 parts by weight of the accelerating agent (e) for the curing reactionof epoxy groups may be contained instead of 0.01 to 25 parts by weightof the component (d), or 0.001 to 2 parts by weight of the component (e)may be contained together with 0.01 to 25 parts by weight of thecomponent (d) in the heat-fusion composition comprising the components(a) and (c), or the components (a), (b) and (c). By the same reasons ashitherto described, the amount of addition of this accelerating agent(e) for the curing reaction of epoxy groups is 0.001 to 2 parts byweight, more preferably 0.01 to 1 parts by weight and especially 0.01 to0.5 parts by weight.

The polyfunctional compound (d) will be described hereinafter. Thepolyfunctional compound (d) is a compound containing at least twofunctional groups reactive to epoxy groups in the molecule, a compoundcontaining at least two functional groups reactive to epoxy groupsselected from an amino group, a carboxylic acid anhydride group, aphenolic hydroxyl group, a carboxyl group and a hydroxyl group beingpreferable.

Examples of the compound containing two or more of amino groups in themolecule are: aliphatic diamines such as 1,6-hexamethylene diamine,trimethylhexamethylene diamine, 1,4-diaminobutane, 1,3-diaminopropane,ethylenediamine and polyether diamine; aliphatic diaminecarbamates suchas hexamethylenediamine carbamate and ethylenediamine carbamate;aliphatic polyamines such as diethylenetriamine, triethylenetetramine,tetraethylenepentamine, pentaethylene-hexamine, ethylaminoethylamine,methylaminopropylamine, 2-hydroxyethylaminopropylamine,aminoethylethanolamine, 1,3-bis(3-aminopropoxy)-2,2-dimethypropane,1,3,6-trisaminomethylhexane, iminobispropylamine,methyliminobispropylamine and bis (hexamethylene) triamine; alicyclicamines such as menthenediamine, N-aminoethylpyperazine,1,3-diamino-cyclohexane, isophoronediamine andbis(4-amino-3-methylcyclohexyl)methane; aliphatic polyamines having anaromatic ring such as m-xylylenediamnie andtetrachloro-p-xylylenediamine; aromatic amines such asm-phenylenediamine, diaminodiphenylether, 4,4-methylenedianiline,diamino-diphenylsulfone, benzidine, 4,4′-bis (o-toluidine),4,4′-thiodianiline, o-phenylenediamine, dianisidine,methylenebis(o-chloroaniline), 2,4-toluenediamine, bis(3,4-diaminophenyl) sulfone, diaminoditolylsulfone,4-chloro-o-phenylenediamine, 4-methoxy-6-methyl-m-phenylenediamine andm-aminobenzylamine; and polyamines containing silicon such as1,3-bis(γ-aminopropyl)-1,1,3,3-tetramethyldisiloxane. Examples of theother amines available are silicone oil modified with amines;butadiene-acrylonitrile copolymers whose terminal functional group is anamine; tertiary amine compounds such asN,N,N′,N′-tetramethylhexamethylenediamine andN,N,N′,N″,N″-pentamethyldiethylenetriamine; ethylene copolymerscomprising an ethylene unit of a copolymer of ethylene and N,N-dimethylaminoethylmethacrylate and α,β-unsaturated carboxylic acidN,N-dialkylaminoalkyl ester unit; ethylene copolymers comprising anethylene unit of the copolymer of ethylene andN,N-dimethylaminopropylacrylamide andN,N-dialkylaminoalkyl-α,β-unsaturated carboxylic acid amide unit;dihydrazide compounds such as succinic acid dihydrazide, adipic aciddihydrazide, isophthalic acid dihydrazide and eicosane dicarbocylic aciddihydrazide; diaminomaleonitrile; and solamine.

Examples of the polyfunctional compounds containing two or more ofcarboxylic acid anhydride groups in a molecule include ethylenecopolymers comprising ethylene units and maleic anhydride units,copolymers of isobutylene and maleic anhydride, and copolymers ofstyrene and maleic anhydride. These copolymers may further containα,β-unsaturated carboxylic acid alkyl esters or carboxylic acid vinylesters—for example alkyl esters of acrylic acid and methacrylic acidsuch as methyl acrylate, ethyl acrylate, butyl acrylate, methylmethacrylate, ethyl methacrylate and butyl methacrylate, and vinylacetate and vinyl propionate—as components of the copolymer. Trimelliticacid anhydride, pyromellitic acid anhydride and ethyleneglycol-bis(anhydrotrimellitate) are also included in the examples.

Examples of the polyfunctional compounds having two or more of phenolichydroxyl groups in a molecule include catechol, resorcin, hydroquinone,Novolac phenol resin, bisphenol A and urethane prepolymers havingphenolic hydroxyl groups at both ends.

Examples of the polyfunctional compounds having two or more of hydroxylgroups in a molecule include saponification products of copolymers ofethylene and vinyl acetate, poly (oxytetramethylene) glycol poly(oxypropylene) glycol, poly (ethyleneadipate) glycol, polyethyleneglycoland polyvinyl alcohol.

Examples of the polyfunctional compounds having two or more of carboxylgroups in a molecule include aliphatic polyfunctional carboxylic acidssuch as oxalic acid, succinic acid, adipic acid, azelaic acid, sebasicacid, dodecanedicarboxylic acid, carbalic acid, cyclohexane-dicarboxylicacid, cyclopentanedicarboxylic acid, ethylene-acrylic acid copolymer,ethylene-methacrylic acid copolymer, ethylene-acrylic acid-methylacrylate copolymer, ethylene-acrylic acid-ethyl acrylate copolymer,ethylene-acrylic acid-butyl acrylate copolymner, ethylene-acrylicacid-vinyl acetate copolymer, ethylene-methacrylic acid-methylmethacrylate copolymer, ethylene-methacrylic acid-ethyl methacrylatecopolymer, ethylene-methacrylic acid-butyl methacrylate copolymer andethylene-methacrylic acid-vinyl acetate copolymer; and aromaticpolyfunctional carboxylic acids such as terephthalic acid, isophthalicacid, orthophthalic acid, naphthalenedicarboxylic acid,biphenyldicarboxylic acid, trimesic acid and trimellitic acid,especially aliphatic polyfunctional carboxylic acids being preferablyused.

Compounds having a plurality of different functional groups includingone or more of carboxyl group, and one or more of functional groupsselected from amino group, carboxylic acid anhydride group, phenolichydroxyl group and hydroxyl group are included in the polyfunctionalcompounds. Examples of them are 4-aminobutyric acid, 6-aminohaxanoicacid, 12-aminododecanoic acid, 4-hydroxybutyric acid, 6-hydroxyhexanoicacid, 12-hydroxydodecanoic acid, 5-hydroxy-barbituric acid,5-aminobarbituric acid, 5-hydroxyimino-barbituric acid and tris(dimethylaminomethyl) phenol. Examples of the polyfunctional compoundshaving one or more of phenolic hydroxyl groups and amino groups areo-aminophenol and m-aminophenol. There is no problem that the foregoingpolyfunctional compounds are used together.

The component (e) will be described hereinafter.

While conventional reaction accelerating agents are available as theaccelerating agent for the curing reaction of epoxy groups, at least oneof the compound selected from tertiary amines, quaternary amine salts,imidazoles, phosphonium salts and organic metal complexes are especiallypreferable.

The tertiary amines include trialkylamines such as triethylamine,tributylamine, trihexylamine and triamylamine; alkanol amines such astriethanol amine and dimethylamino-ethanol; aliphatic or non-aromaticcyclic amines such as triethylenediamine; aromatic amines such asdimethylphenyl-amine, dimethylbenzylamine,2-(dimethylaminomethyl)phenol, 2,4,6-tris(dimethylaminomethyl)phenol,dimethylaniline; alicyclic amines such as pyridine, picoline and1,8-diazabicyclo(5.4.0)undecene-1; and salts of these tertiary amineswith organic acids or inorganic acids.

Examples of the quaternary amine salts are tetraalkyl-ammonium halide(for example tetra-(C1 to 6)-alkylammonium halides such astetramethylammonium chloride, tetraethyl-ammonium chloride, andtetrabutylammonium bromide), trialkylaralkylammonium halide (for exampletri-(C1 to 6)-alkyl-(C7 to 10)-alalkylammonium halide such astrimethylbenzyl-ammonium chloride, triethylbenzylammonium chloride andtripropylbenzylammonium chloride) and N-alkylpyridinium halide (forexample N-methylpyridinium chloride).

Examples of imidazoles are 2-(C1 to 18)-alkylimidazoles such as2-methylimidazole, 2-ethylimidazole and 2-isopropylimidazole;2-arylimidazoles such as 2-phenylimidazole; imidazole compounds havingalkyl groups or aryl groups at 2- and/or 4-position such as2-ethyl-4-methylimidazole and 4-phenyl-2-methylimidazole; imidazolecompounds such as cyanoethylated imidazole and cyanoethylated imidazolecompounds converted into triazine; and salts of these imidazolecompounds (for example trimellitic acid salts or isocyanuric acidsalts).

Phosphonium salts include tetraalkylphosphonium halides (for exampletetra-(C1 to 6) alkylphosphonium halides such as tetramethylphosphoniumbromide and tetrabutylphosphonium bromide), tetrabutylphosphoniumbenzotriazalate, tetraarylphosphonium halide (for exampletetraphenyl-phosphonium bromide), ethyltriphenylphosphonium bromide andtriphenylbenzylphosphonium bromide.

Examples of the organic metal complexes are tin compounds (for exampledibutyl tin dilaurate) and titanium compounds (for exampletriisopropoxymethyl titanate).

Of these accelerating agents (e) for the curing reaction of epoxygroups, tertiary amines such as dimethylphenylamine, quaternary aminessuch as triethylbenzylammonium chloride, phosphonium salts such astetrabutylphosphonium bromide and tetraphenylphosphonium bromide, andtin compounds such as dibutyl tin dilaurate are preferably used in thepresent invention.

The multi-layer molded body comprising the foregoing heat-fusioncomposition and the other layer will be described hereinafter.

The layer comprising the heat-fusion composition according to thepresent invention has a good adhesive property with the other layer.

Examples of the other layer are paper, cloths, metals, woods,heat-curing reins, thermoplastic resins and elastomers. The multi-layermolded body according to the present invention preferably containsheat-curing resins or thermoplastic resins as the other layer. The layerhas an excellent heat-fusion property with the layer comprising at leastone kind of resin selected from hard resins such as ABS resin, impactresistant polystyrene, polycarbonate, polymethylmethacrylate,polypropylene, saturated polyester resins, polyamide, polyvinyl chlorideand polyphenylene oxide resin. The hard resin as used herein may be thesame or different hard resin as used in the constituting component ofthe heat-fusion composition according to the present invention.

The heat-fusion property of the multi-layer molded body according to thepresent invention is more enhanced to obtain a more robust multi-layermolded body owing to a reaction with epoxy groups in the heat-fusioncomposition containing the epoxydized block copolymer (a), by allowing0.01 to 25 parts by weight of the foregoing polyfunctional compound (d)containing at least two functional groups, selected from amino group,carboxylic acid anhydride group, phenolic hydroxyl group, carboxyl groupand hydroxyl group, reactive to epoxy groups to contain in 100 parts byweight of the hard resin as a layer comprising the hard resin.

A layer formed by allowing 0.01 to 25 parts by weight of the foregoingpolyfunctional compound (d) containing at least two functional groups,selected from amino group, carboxylic acid anhydride group, phenolichydroxyl group, carboxyl group and hydroxyl group, reactive to epoxygroups, and/or 0.001 to 2 parts by weight of the foregoing acceleratingagent (e) for the curing reaction of epoxy groups to contain in 100parts by weight of the hard resin may be used as a layer comprising thehard resin in the multi-layer molded body according to the presentinvention. A higher heat-fusion property can be obtained by acceleratingthe reaction of epoxy groups in the heat-fusion composition.

A method for kneading fused resins with a biaxial extruder is used forthe method for producing the heat-fusion composition according to thepresent invention. The epoxydized block copolymer as the component (a),the elastomer as the component (b), and the hard resin (c) and/or theaccelerating agent (e) for the curing reaction of epoxy groups and/orthe polyfunctional compound (d), if necessary, may be fused and kneadedtogether. After feeding the components (a) and (b) into the biaxialextruder at first to be fused and kneaded, (c) and/or (d) and/or (e)maybe fed to be fused and kneaded in the next step.

When a hard resin composition is obtained by kneading the polyfunctionalcompound (d) and/or accelerating agent (e) for the curing reaction ofepoxy groups with the hard resin, the polyfunctional compound (d) and/oraccelerating agent (e) for the curing reaction of epoxy groups may befused and kneaded together with the hard resin as in the usual methodfor producing the heat-fusion composition. Otherwise, the component (e)may be fed to fuse and knead in the second step after firstly feedingthe hard resin and the component (d) to the biaxial extruder for fusionand kneading.

Kneading machines such as conventionally used uniaxial or biaxialextruders, a banbury mixer, rolls and various kind of kneaders can beused for fusion-kneading.

Additives such as pigments, dyes, reinforcers, inorganic fillers, heatstabilizers, anti-oxidants, anti-weathering agents, core materials,lubricants, anti-static agents, flame retardants, plasticizers, foamingagents and oils, or other polymers may be added and blended with thehard resin constituting the heat-fusion composition according to thepresent invention or the multi-layer molded body comprising the same,provided that the additives do not compromise the molding ability andphysical properties of the composition. Among these additives other thanessential components, an oil is known to be a useful additive foradjusting the molding ability, softness and surface hardness. The oilsavailable in the present invention are the oils classified into paraffinand naphthene oils. Examples of the available inorganic fillers arecalcium carbonate, silica, talk, clay, titanium oxide, carbon black,barium sulfate, zinc oxide, magnesium hydroxide, mica, glass flakes,glass fiber, glass beads, glass balloon, stainless steel fiber andalumina.

An injection molding machine, extruder, blow molding machine or acombined molding machine thereof is used for molding the heat-fusioncomposition and hard resin according to the present invention into amulti-layers. A method for using a double (or two color) molding machineand an insert molding method are used in molding different materialsinto a multi-layers using an injection molding machine. In the methodusing the double injection molding machine, a die for the primarymaterial (a hard resin) and a die for the secondary material (aheat-fusion composition) are disposed to alternately extrude thedifferent resins from the two heated cylinders. A die for the doublemolding is classified into core-rotation method and core-back method. Inthe core-rotation method, only the movable part of the primary materialdie is rotated by 180° C. to make the primary molded body molded atfirst to transfer to the cavity part of the secondary material die to beused in the subsequent injection and, after forming a space for fillingthe secondary material following die clamping, the secondary material isfilled into the space to subject to heat-fusion, thereby obtaining amulti-layer molded body. In the core-back method, on the other hand, aslide core is assembled in the die to firstly inject the primarymaterial by allowing the core to advance and, after allowing the core torecede, the secondary material is injected into the cavity formed tosubject to heat-fusion, thereby obtaining a multi-layer molded body. Acombined method of these two methods has been developed, or a method forsimultaneously obtaining the multi-layer molded body from the twocylinders are being developed. The multi-layer molded body according tothe present invention may be produced by the method using the doublemolding machine, irrespective of the methods.

In the method by the insert molding, the primary material is previouslymolded, which is inserted into the die followed by injecting thesecondary material to make the first and second materials to heat-fuseto obtain a multi-layer molded body. Although this method is favored inits low die cost, the degree of molecular interlock between the primaryand secondary materials is low since the surface of the primary materialhas been already hardened, exhibiting a low heat-fusion property. Whilea multi-layer molded body having a high heat-fusion property is expectedby using the method described above, this insert molding method is madepossible to obtain a multi-layer molded body having a high heat-fusionproperty in the present invention.

Conventional multi-layer extrusion molding machine is used in the methodfor molding different materials into a multi-layers using an extrusionmolding machine. The method for molding different materials into amulti-layer using a blow molding machine is classified into two methodsof multi-layer extrusion blow molding in which parisons are formed byco-extrusion and multi-layer injection blow molding in which parisonsare formed by co-injection. The method for using the conventionalmulti-layer extrusion blow molding machine can be used for themulti-layer molded body according to the present invention irrespectiveof the methods.

EXAMPLE

While the present invention will be described hereinafter in more detailreferring to the examples, the present invention is not limited theretoin any sense. (Method of measurement)

The physical properties in the examples were measured as follows.

Heat fusion property (1): A plate with a dimension of 60 mm in length,25 mm in width and 2 mm in thickness was molded using a hard resinconstructing the multi-layer molded body according to the presentinvention with a injection molding machine. This plate was inserted intoa die to mold a heat-fusion composition according to the presentinvention on this plate by injection, thereby producing a test piecewith a dimension of 127 mm in length, 25 mm in width and 8 mm inthickness. The surface temperature of the inserted plate was 20° C. Theheat-fusion strength was measured by a tensile test such that one end ofthe heat fusion composition of the test piece was bent at an angle of90° against one end of the same side of the hard resin of the testpiece. The tension speed was 5 nun/min. In other word, the test piecewas subjected to a 90° mold release strength measurement with a width of25 mm. The unit of the heat-fusion property is in kg/25 mm.

Heat-fusion property (2): A plate with an width of 100 mm and thicknessof 8 mm was continuously extruded with a dual-layer extruder having twocylinders. The thickness of the hard resin layer is 2 mm while thethickness of the heat-fusion composition is 6 mm. This plate was cut offto prepare a test piece having a thickness of 25 mm and the heat-fusionstrength was measured by a tensile test such that one end of the heatfusion composition of the test piece was bent at an angle of 90 againstone end of the same side of the hard resin of the test piece. Thetension speed was 5 mm/min. The unit of the heat-fusion property is inkg/25 mm as described above.

Surface hardness: The hardness was measured with a hardness meteraccording to JIS K-6301 type A.

Mold release property: Mold release property from the injection moldingdie or touch roll of the extrusion molding was visually observed. Theproperty was evaluated by a mark (×) (some problem in mold release) or(∘) (no problem in mold release).

Gel: The appearance of the heat-fusion composition layer was visuallyobserved with respect to roughness due to gel formation, wherein themark (×) denotes that the surface lost glossiness due to roughness bygel formation and the mark (∘) denotes that there was no roughness.

Reference Example 1

Method for producing epoxydized block copolymer (a-1)

In a reaction vessel equipped with a jacket and provided with a stirrer,reflux condenser and thermometer, 400 g of a hydrogenatedstyrene-butadiene block copolymer (made by Asahi Kasei Co., TaftecH-1041) and 1,500 g of cyclohexane were placed and the mixture wassubjected to an epoxydation reaction at 50° C. for 3 hours with stirringwhile continuously adding 39 g of 30 wt % peracetic acid solution inethyl acetate dropwise. The reaction solution was taken out of thereaction vessel after cooling the solution at room temperature and,after washing the reaction solution with water, the solvent was removedby a steam stripping to obtain an epoxydized block copolymer. Thisepoxydized block copolymer obtained is referred to a copolymer (a-1).The epoxy equivalent of this copolymer is 5,340.

Reference Example 2

Method for producing epoxydized block copolymer (a-2)

In a reaction vessel equipped with a jacket and provided with a stirrerand thermometer, 300 g of a polystyrene-polybutadiene-polystyrene blockcopolymer (made by Nihon Synthetic Rubber Co., trade name: TR2000) wasdissolved in 3,000 g of cyclohexane. A hydrogenation catalysts—a mixtureprepared by mixing 40 ml of a cyclohexane solution of di-p-tolylbis(1-cyclopentadienyl) titanium (with a concentration of 1millimole/litter) and 8 ml of n-butyllithium solution (with aconcentration of 5 millimole/litter) at 0° C. under a hydrogen pressureof 2.0 kg/cm²—was added to the foregoing solution to allow the mixtureto react at 60° C. under a hydrogen pressure of 2.5 kg/cm² for 30minutes. The solvent was removed from the partially hydrogenated polymersolution by vacuum drying (the degree of hydrogenation of the totalbutadiene portion was 30%). Dissolved was 300 g of this partiallyhydrogenated polymer in 1,500 g of cyclohexane. Then, an epoxydationreaction was carried out by continuously adding 300 g of 30 wt %peracetic acid solution in ethyl acetate dropwise with stirring at 40°C. for 3 hours. The reaction solution was taken out of the reactionvessel after cooling the solution at room temperature and the polymerwas precipitated by adding a large amount of methanol in the reactionsolution. An epoxydized block copolymer was obtained by filtrating theprecipitate off followed by washing with water and drying. Theepoxydized block copolymer obtained is referred to the copolymer (a-2).The epoxy equivalent of this polymer is 275.

Reference Example 3

Method for producing epoxydized block copolymer (a-3)

In a reaction vessel equipped with a jacket and provided with a stirrer,reflux condenser and thermometer, 300 g of apolystyrene-polybutadiene-polystyrene block copolymer (made by NihonSynthetic Rubber Co., trade name: TR2000) was dissolved in 1,500 g ofethyl acetate. An epoxydation reaction was carried out by continuouslyadding 169 g of 30 wt % peracetic acid solution in ethyl acetatedropwise at 40° C. for 3 hours with stirring. The reaction solution wastaken out of the reaction vessel after cooling the solution at roomtemperature and the polymer was precipitated by adding a large amount ofmethanol. The precipitate was filtered, washed with water and dried toobtain a epoxydized polymer (a-3). The epoxy equivalent of theepoxydized block copolymer obtained was 470.

The constituting components used in the present invention are asfollows:

a-1: a hydrogenated epoxydized block copolymer with an epoxy equivalentof 5,340;

a-2: an epoxydized block copolymer with an epoxy equivalent of 275;

a-3: an epoxydized block copolymer with an epoxy equivalent of 470;

b-1: “Septon 2002” made by Kurarey Co., a hydrogenated styrene-isopreneblock copolymer (SEPS);

b-2: “Lezamine P4038” made by Dainihon Seika Kogyo Co., acaprolactone-polyurethane based elastomer;

b-3: “Neubelane P4110AN” made by Teijin Co., a PBT-ether based polyesterelastomer;

b-4: “Pebacks 4033S” made by At-Chem Co., a nylon based elastomer;

b-5: “Santplane 201-73” made by AES Japan Co., a polyolefin basedelastomer having ethylene-propylene rubber as a soft segment and PP as ahard segment;

b-6: “Sunplane 7206” made by Mitsubishi Kagaku MKV Co., a polyvinylchloride based elastomer;

c-1: “Sebian 510” made by Daicel Kagaku Kogyo Co., ABS resin;

c-2: “Daicel Styrol R81” made by Daicel Kagaku Kogyo Co., an impactresistant polystyrene;

c-3: “Panlite L1225” made by Teijin Co., a polycarbonate resin;

c-4: “AcrypetMD” made by Mitsubishi Rayon Co., polymethylmethacrylate;

c-5: “Noblen D501” made by Sumitomo Kagaku Kogyo Co., polypropylene;

c-6: “Juranex400FP” made by Polyplastic Co., polybutylene-terephthalate;

c-7: “Sin-etsu PVCTK 600” made by Shin-etsu Kagaku Kogyo Co., polyvinylchloride;

c-8: “Nylon 1013B” made by Ube Kosan Co., nylon 6;

c-9: “Nolyl 731” made by Nihon GE Plastics Co., a modified polyphenyleneether resin;

d-1: “PEO Amine 6000” made by Kawaken Fine Chemical Co.,polyethyleneoxidediamine;

d-2: “Bondine AX 8000” made by Sumitomo Kagaku Kogyo Co., anethylene-maleic anhydride-ethyl acrylate copolymer, content of themaleic anhydride-ethyl acrylate comonomer=5% by weight;

d-3: “Sumiaid 300G” made by Sumitomo Kagaku Kogyo Co., a saponificationproduct of an ethylene-vinyl acetate copolymer;

d-4: “Neukrel N1035” made by Mituis Du Pont Polychemical Co., anethylene-methacrylic acid copolymer containing 10% by weight ofmethacrylic acid;

e-1: diphenylamine;

e-2: triethylbenzylammonium chloride;

e-3: dibutyl tin dilaurate.

Example 1 to 16

Each heat-fusion composition and hard resin were heat-fused with eachother in the blending proportions shown in TABLE 1 to 2 and TABLE 3 to 4using the epoxydized block copolymer (a-l) with a dual-layer extrusionmolding machine with a diameter of 30 mm. The results of measurementswere as shown in Table 3 to 4. The heat-fusion property tends to behigher when the blending proportion of the epoxydized block copolymer islarger with a few exceptions.

Example 17 to 41

Each heat-fusion composition and hard resin were heat-fused with eachother in the blending proportions shown in TABLE 5 to 7 and TABLE 8 to10 using the epoxydized block copolymer (a-2) by a injection moldinginsert method. The results of measurements were as shown in TABLE 8 to10. Although the heat-fusion property is speculated to be low in theinsert molding with a low surface temperature of the primary material (ahard resin) since the degree of molecular interlock with the secondarymaterial (a heat-fusion composition) is small, the multi-layer moldedbody according to the present invention exhibits a high heat-fusionproperty.

Example 42 to 71

Each heat-fusion composition and hard resin were heat-fused with eachother in blending proportions shown in TABLE 11 to 13 and TABLE 14 to 16using the epoxydized block copolymer (a-3) with an injection moldingmachine. The results of measurements were as shown in TABLE 14 to 16.The epoxydized block copolymer (a-3) having a higher epoxy equivalenttends to have a little lower heat-fusion property than the epoxydizedblock copolymer (a-2) since the former has a lower epoxy concentrationthan the latter.

Comparative Example 1 to 9

Each heat-fusion composition and hard resin were heat-fused with eachother in the blending proportions shown in TABLE 17 and TABLE 18 usingthe epoxydized block copolymer (a-1) with a dual extrusion moldingmachine with a diameter of 30 mm. The results of measurements were asshown in TABLE 18. The heat fusion property becomes lower in the samplewith a blending ratio of the epoxydized block copolymer of less than 20%by weight. When the blending ratio of the epoxydized block copolymerexceeds 80% by weight, on the other hand, mold release property from thetouch roll in the extrusion molding becomes of problem. When theblending amount to be added in the heat-fusion composition is too large,the surface hardness becomes so high that a good feeling of theelastomer is lost. When the blending amount of the polyfunctionalcompounds to be added in the heat-fusion composition is too large, alarge amount of gel tends to appear to impair good appearance.

Comparative Example 10 to 18

Each heat-fusion composition and hard resin were heat-fused with eachother in the blending proportions shown in TABLE 19 and TABLE 20 usingthe epoxydized block copolymer (a-2) with an injection molding machine.

The results of the measurements were as shown in TABLE 20. The sameresults as shown in Comparative example 1 to 9 were observed when theepoxy equivalent of the epoxydized block copolymer was changed and theprocessing method was changed to an injection molding insert. When theamount of use of the accelerating agent for the curing reaction of epoxygroups exceeds 2 parts by weight, gel formation was increased therebyimpairing the appearence.

Example 19 to 27

Each heat-fusion composition and hard resin were heat-fused with eachother in the blending proportions shown in TABLE 21 and TABLE 22 usingthe epoxydized block copolymer (a-3) with an injection molding machine.The results of the measurements were as shown in TABLE 22. The sameresults as shown in Comparative example 10 to 18 were observed when theepoxy equivalent of the epoxydized block copolymer was changed.

Industrial Applicability

As disclosed herein, a multi-layer molded body having an excellentheat-fusion property can be obtained by heat-fusing the heat-fusioncomposition blended with the epoxydized block copolymer according to thepresent invention with the hard resin. Although the heat-fusion propertyis usually speculated to be low especially in the insert molding with alow surface temperature of the primary material (a hard resin) since thedegree of molecular interlock with the secondary material is small, themulti-layer molded body according to the present invention has a highheat-fusion property even in this case. The molded bodies obtained canbe used for a turn table of a CD-ROM driver, a side braid of the door ofa car, clips and handles of the electric appliances, spacers, packings,air bag covers, push buttons of the key board of a personal computer,sound damping gear and sports shoes sole and so on.

TABLE 1 Example 1 2 3 4 5 6 7 8 9 10 Heat-fusion *1 a-1 60 70 80 40 4080 80 60 70 50 composition (a) a-2 a-3 *2 b-1 60 50 (b) b-2 40 60 30 b-320 b-4 20 b-5 30 40 b-6 20 *3 c-1 30 (c) c-2 c-3 c-4 c-5 40 30 c-6 20c-7 c-8 20 c-9 *4 d-1 (d) d-2 20 d-3 d-4 *5 e-1 (e) e-2 e-3 *1 (a):Epoxydized copolymer, the figures are expressed in % by weight, ((a) +(b)) is equal to 100% by weight. *2 (b): Thermoplastic elastomer, thefigures are expressed in % by weight, ((a) + (b)) is equal to 100% byweight. *3 (c): Hard resin, the figures correspond to parts by weightper 100 parts by weight of ((a) + (b)). *4 (d): Polyfunctional compound,the figures correspond to parts by weight per 100 parts by weight of((a) + (b)). *5 (e): Epoxy reaction accelerating agent, the figurescorrespond to parts by weight per 100 parts by weight of ((a) + (b)).

These abbreviations are commonly used in TABLE 1 to TABLE 22.

TABLE 2 Example 11 12 13 14 15 16 Heat-fusion composition (a) a-1 30 5050 20 40 50 a-2 a-3 (b) b-1 70 80 50 b-2 50 b-3 50 b-4 b-5 60 b-6 (c)c-1 c-2 c-3 50 c-4 c-5 c-6 c-7 c-8 c-9 20 (d) d-1 2 d-2 10 d-3 10 d-4 2020 (e) e-1 0.1 e-2 0.1 e-3

TABLE 3 Example 1 2 3 4 5 6 7 8 9 10 Hard resin (c) c-1 100  100 composition c-2 c-3 100  100  c-4 100 c-5 100  100  c-6 100  c-7 c-8 100c-9 100  (d) d-1 10 d-2 10 20 d-3 d-4 20 (e) e-1 0.5 e-2  1  1 e-3 Heatfusion property (1) — — — — — — — — — — Heat fusion property (2) 15 2016 13 17 14 13 12 13 18 Surface hardness (A) 70 70 70 70 65 70 80 75 7065 Mold release property ∘ ∘ ∘ ∘ ∘ ∘ ∘ ∘ ∘ ∘ Gel ∘ ∘ ∘ ∘ ∘ ∘ ∘ ∘ ∘ ∘

TABLE 4 Example 11 12 13 14 15 16 Hard resin (c) c-1 composition c-2100  100  c-3 100  100  c-4 c-5 c-6 100  c-7 c-8 c-9 100  (d) d-1 d-2 10d-3 d-4 20 (e) e-1 0.01 e-2 e-3  1 Heat fusion property (1) — — — — — —Heat fusion property (2) 14 22 12 13 15 20 Surface hardness (A) 85 65 8070 70 70 Mold release property ∘ ∘ ∘ ∘ ∘ ∘ Gel ∘ ∘ ∘ ∘ ∘ ∘

TABLE 5 Example 17 18 19 20 21 22 23 24 25 26 Heat-fusion (a) a-1composition a-2 30 30 50 40 40 30 20 50 60 30 a-3 (b) b-1 80 70 b-2 70b-3 70 60 50 b-4 70 b-5 50 60 b-6 40 (c) c-1 c-2 c-3 c-4 c-5 c-6 c-7 c-830 c-9 (d) d-1 d-2 20 d-3 d-4 20 (e) e-1 e-2 e-3

TABLE 6 Example 27 28 29 30 31 32 33 34 35 36 Heat-fusion (a) a-1composition a-2 30 20 40 50 50 20 30 60 50 40 a-3 (b) b-1 60 70 60 b-280 b-3 50 50 b-4 40 b-5 70 80 b-6 50 (c) c-1 c-2 40 c-3 c-4 c-5 30 20c-6 40 c-7 20 c-8 20 40 c-9 (d) d-1 d-2 d-3 d-4 (e) e-1 e-2 e-3

TABLE 7 Example 37 38 39 40 41 Heat-fusion (a) a-1 composition a-2 80 5070 50 60 a-3 (b) b-1 20 50 40 b-2 50 b-3 b-4 b-5 b-6 30 (c) c-1 c-2 c-3c-4 c-5 10 c-6 c-7 c-8 c-9 (d) d-1 d-2 d-3 d-4 10 (e) e-1 e-2 e-3

TABLE 8 Example 17 18 19 20 21 22 23 24 25 26 Hard resin (c) c-1composition c-2 c-3 100  c-4 100  c-5 100  100   c-6 100  100  c-7 100 c-8 100 100  c-9 100  (d) d-1 d-2 20 10 d-3 10 d-4 20 (e) e-1 0.1 e-20.1 e-3 Heat fusion property (1) 12 12 11 11 12  9 8 11 12 12 Heatfusion property (2) — — — — — — — — — — Surface hardness (A) 65 80 65 6575 80 66 75 65 65 Mold release ∘ ∘ ∘ ∘ ∘ ∘ ∘ ∘ ∘ ∘ Gel ∘ ∘ ∘ ∘ ∘ ∘ ∘ ∘ ∘∘

TABLE 9 Example 27 28 29 30 31 32 33 34 35 36 Hard resin (c) c-1 100composition c-2 100  c-3 100  c-4 c-5 100  100  c-6 100  c-7 100  c-8100  100  c-9 100  (d) d-1 d-2 20 d-3 d-4 10 (e) e-1 0.1 e-2 e-3  1  1Heat fusion property (1)  8 7 12  6 13  6 11  7 10  8 Heat fusionproperty (2) — — — — — — — — — — Surface hardness (A) 75 75 65 80 75 7065 80 70 75 Mold release property ∘ ∘ ∘ ∘ ∘ ∘ ∘ ∘ ∘ ∘ Gel ∘ ∘ ∘ ∘ ∘ ∘ ∘∘ ∘ ∘

TABLE 10 Example 37 38 39 40 41 Hard resin (c) c-1 100  composition c-2100  100  c-3 100  c-4 100  c-5 c-6 c-7 c-8 c-9 (d) d-1 d-2 d-3 d-4 (e)e-1 e-2 e-3  1 Heat fusion property (1) 16 13 14 11 13 Heat fusionproperty (2) — — — — — Surface hardness (A) 65 65 65 65 65 Mold releaseproperty ∘ ∘ ∘ ∘ ∘ Gel ∘ ∘ ∘ ∘ ∘

TABLE 11 Example 42 43 44 45 46 47 48 49 50 51 Heat-fusion (a) a-1composition a-2 a-3 40 80 40 40 40 40 40 40 40 30 (b) b-1 60 60 60 60b-2 60 b-3 60 60 b-4 60 b-5 70 b-6 20 (c) c-1 20 c-2 50 c-3 c-4 c-5 30c-6 40 c-7 c-8 30 c-9 (d) d-1 10 d-2 d-3 d-4 20 (e) e-1 e-2 e-3

TABLE 12 Example 52 53 54 55 56 57 58 59 60 61 Heat-fusion (a) a-1composition a-2 a-3 50 50 60 50 50 70 50 50 50 80 (b) b-1 50 50 50 b-240 50 b-3 50 50 b-4 20 b-5 50 b-6 30 (c) c-1 c-2 30 c-3 c-4 c-5 50 c-650 c-7 c-8 c-9 (d) d-1 d-2 10 d-3 d-4 (e) e-1 e-2 e-3

TABLE 13 Example 62 63 64 65 66 67 68 69 70 71 Heat-fusion (a) a-1composition a-2 a-3 80 70 60 80 60 70 60 60 50 70 (b) b-1 20 40 50 30b-2 40 b-3 30 40 b-4 20 30 b-5 b-6 40 (c) c-1 c-2 c-3 c-4 c-5 c-6 20 c-720 c-8 40 c-9 (d) d-1 d-2 d-3 10 d-4 (e) e-1 e-2 e-3

TABLE 14 Example 42 43 44 45 46 47 48 49 50 51 Hard resin (c c-1 100 100 composition c-2 100  c-3 100  c-4 100  c-5 100  c-6 100  c-7 100 c-8 100  c-9 100  (d d-1 d-2 d-3 d-4 (e e-1 0.1 e-2 e-3 0.5 Heat fusionproperty (1) 9 15  6 12  9 11 11  7 10 10 Heat fusion property (2) — — —— — — — — — — Surface hardness (A) 80 65 80 65 70 80 65 80 65 70 Moldrelease property ∘ ∘ ∘ ∘ ∘ ∘ ∘ ∘ ∘ ∘ Gel ∘ ∘ ∘ ∘ ∘ ∘ ∘ ∘ ∘ ∘

TABLE 15 Example 52 53 54 55 56 57 58 59 60 61 Hard resin (c) c-1 100composition c-2 100 c-3 100  100  c-4 100  c-5 100  c-6 100  c-7 100 c-8 100  c-9 100  (d) d-1 d-2 d-3 d-4 (e) e-1 e-2 0.1 e-3 0.1 0.1 Heatfusion property (1) 12  7 10 6  9 11 14 10 10 14 Heat fusion property(2) — — — — — — — — — — Surface hardness (A) 65 80 65 80 85 65 70 75 6570 Mold release property ∘ ∘ ∘ ∘ ∘ ∘ ∘ ∘ ∘ ∘ Gel ∘ ∘ ∘ ∘ ∘ ∘ ∘ ∘ ∘ ∘

TABLE 16 Example 62 63 64 65 66 67 68 69 70 71 Hard resin (c) c-1 100 100  100  composition c-2 100  100 c-3 100  c-4 c-5 c-6 100  c-7 100 c-8 100  c-9 100  (d) d-1 d-2 10 d-3 10 d-4 (e) e-1 e-2 e-3 0.1 Heatfusion property (1) 14 12 10 17 10 11 10 11 11 14 Heat fusion property(2) — — — — — — — — — — Surface hardness (A) 65 70 80 65 65 80 70 65 6565 Mold release property ∘ ∘ ∘ ∘ ∘ ∘ ∘ ∘ ∘ ∘ Gel ∘ ∘ ∘ ∘ ∘ ∘ ∘ ∘ ∘ ∘

TABLE 17 Comparative example 1 2 3 4 5 6 7 8 9 Hard resin (a) a-1 10 1010 10 10 10 90 90 70 composition a-2 a-3 (b) b-1 90 10 10 b-2 90 b-3 90b-4 90 b-5 90 30 b-6 90 (c) c-1 c-2 60 c-3 c-4 c-5 c-6 c-7 c-8 20 c-9(d) d-1 d-2 40 d-3 d-4 (e) e-1 e-2 e-3

TABLE 18 Comparative example 1 2 3 4 5 6 7 8 9 Hard resin (c) c-1 100 100  composition c-2 100 c-3 c-4 100  c-5 100  c-6 100  c-7 100  c-8 100c-9 100  (d) d-1 20 d-2 d-3 d-4 (e) e-1 0.5 e-2 e-3 0.5 Heat fusionproperty (1) — — — — — — — — — Heat fusion property (2) 4  4  2 4  2  521 17 14 Surface hardness (A) 65 65 100 100 65 65 65 95 70 or or moremore Mold release property ∘ ∘ ∘ ∘ ∘ ∘ x ∘ ∘ Gel ∘ ∘ ∘ ∘ ∘ ∘ ∘ ∘ x

TABLE 19 Comparative example 10 11 12 13 14 15 16 17 18 Hard resin (a)a-1 composition a-2 10 10 10 10 10 10 90 90 80 a-3 (b) b-1 90 10 20 b-290 b-3 90 10 b-4 90 b-5 90 b-6 90 (c) c-1 c-2 c-3 c-4 c-5 c-6 60 c-7 c-8c-9 (d) d-1 d-2 d-3 d-4 (e) e-1 e-2 e-3  3

TABLE 20 Comparative example 10 11 12 13 14 15 16 17 18 Hard resin (c)c-1 100  composition c-2 c-3 c-4 c-5 100  c-6 100  100  c-7 100  c-8100  100  c-9 100  100  (d) d-1 20 d-2 d-3 d-4 (e) e-1 0.1 0.5 e-2 e-30.5 Heat fusion property (1)  3 2  2 4 2  3 19 11 12 Heat fusionproperty (2) — — — — — — — — — Surface hardness (A) 65 65 100  100 65 6565 95 75 Mold release property ∘ ∘ ∘ ∘ ∘ ∘ x ∘ ∘ Gel ∘ ∘ ∘ ∘ ∘ ∘ ∘ ∘many

TABLE 21 Comparative example 19 20 21 22 23 24 25 26 27 Hard resin (a)a-1 composition a-2 a-3 10 10 10 10 10 10 90 80 80 (b) b-1 90 20 b-2 9010 b-3 90 20 b-4 90 b-5 90 b-6 90 (c) c-1 c-2 70 c-3 c-4 c-5 c-6 c-7 c-8c-9 (d) d-1 d-2 d-3 d-4 (e) e-1 e-2  3 e-3

TABLE 22 Comparative example 19 20 21 22 23 24 25 26 27 Hard resin (c)c-1 100  100  composition c-2 100 100 100 c-3 c-4 c-5 100 c-6 100  c-7100  c-8 100 c-9 (d) d-1 d-2 20 20 d-3 d-4 (e) e-1 0.1 0.5 e-2 e-3 0.50.5 0.5 0.5 Heat fusion property (1)  2 3  3 4 1  2 18 10 11 Heat fusionproperty (2) — — — — — — — — — Surface hardness (A) 65 65 100  100 65 6570 85 95 Mold release property ∘ ∘ ∘ ∘ ∘ ∘ x ∘ ∘ Gel ∘ ∘ ∘ ∘ ∘ ∘ ∘ x ∘

What is claimed is:
 1. A heat-fusion composition for molding intomulti-layers comprising 20 to 80% by weight of a block copolymer havingepoxy groups (a), which is an epoxidized block copolymer obtained byepoxiding (i) a block copolymer comprising a polymer block mainlycomposed of a vinyl aromatic hydrocarbon compound and a polymer blockmainly composed of a conjugalated diene compound, or (ii) thehydrogenated product of said block copolymer, wherein the epoxidation iseffected by peroxidation of the ethylenic double bonds and the epoxyequivalent of the epoxidized block copolymer is 140 to 10,000, and 80%to 20% by weight of at least one kind of thermoplastic elastomer (b)selected from the group consisting of styrene elastomers, polyurethaneelastomer, polyester elastomers, polyamide elastomers, polyolefinelastomers and polyvinyl chloride elastomers, the combined content of(a) and (b) being 100% by weight.
 2. The heat-fusion composition formolding into multi-layers as claimed in claim 1, further comprising 10to 50 parts by weight of (c) at least one kind of hard resin selectedfrom the group consisting of an ABS resin, impact resistant polystyrene,polycarbonate, polymethylmethacrylate, polypropylene, saturatedpolyester resin, polyamide, polyvinyl chloride and polyphenylene oxideresin per 100 parts by weight of (a) and (b).
 3. A heat-fusioncomposition for molding into multi-layers comprising 20 to 80% by weightof a block copolymer having epoxy groups (a), which is an epoxidizedblock copolymer obtained by epoxiding (i) a block copolymer comprising apolymer block mainly composed of a vinyl aromatic hydrocarbon compoundand a polymer block mainly composed of a conjugated diene compound, or(ii) the hydrogenated product of said block copolymer, wherein theepoxidation is effected by peroxidation of the ethylenic double bondsand the epoxy equivalent of the epoxidized block copolymer is 140 to10,000. and 80% to 20% by weight of at least one kind of thermoplasticelastomer (b) selected from the group consisting of styrene elastomers,polyurethane elastomer, polyester elastomers, polyamide elastomers,polyolefin elastomers and polyvinyl chloride elastomers, the combinedcontent of (a) and (b) being 100% by weight and said composition furthercomprising 0.01 to 25 parts by weight of (d) a polyfunctional compoundcontaining at least two functional groups reactive to the epoxy group ina molecule and/or 0.001 to 2 parts by weight of (e) an acceleratingagent for the curing reaction of epoxy groups per 100 parts by weight of(a) and (b).
 4. The heat-fusion composition for molding intomulti-layers according to claim 3, wherein (d) the polyfunctionalcompound is a polyfunctional compound containing at least two identicalor different functional groups, selected from the group consisting of anamino group, carboxylic acid anhydride group, phenolic hydroxyl group,hydroxyl group and carboxyl group, in the molecule.
 5. The heat-fusioncomposition for molding into multi-layers according to claim 3, wherein(e) the accelerating agent for the curing reaction of epoxy groups is atleast one kind of compound selected from the group consisting oftertiary amines, quaternary amine salts, imidazoles, phosphonium saltsand organometallic complexes.
 6. A heat-fusion composition for moldinginto multi-layers comprising 20 to 80% by weight of a block copolymerhaving epoxy groups (a), which is an epoxidized block copolymer obtainedby epoxidizing (i) a block copolymer comprising a polymer block mainlycomposed of a vinyl aromatic hydrocarbon compound and a polymer blockmainly composed of a conjugated diene compound, or (ii) the hydrogenatedproduct of said block copolymer, wherein the epoxidation is effected byperoxidation of the ethylenic double bonds and the epoxy equivalent ofthe epoxidized block copolymer is 140 to 10,000, and 80 to 20% by weightof at least one kind of thermoplastic elastomer (b) selected from thegroup consisting of styrene elastomers, polyurethane elastomers,polyester elastomers, polyamide elastomers, polyolefin elastomers andpolyvinyl chloride elastomers, the combined content of (a) and (b) being100% by weight and said composition further comprising 10 to 50 parts byweight of (c) at least one kind of hard resin selected from the groupconsisting of an ABS resin, impact resistant polystyrene, polycarbonate,polymethacrylate, polypropylene, saturated polyester resin, polyamide,polyvinyl chloride and polyphenylene oxide resin, 0.01 to 25 parts byweight of (d) a polyfunctional compound containing at least twofunctional groups reactive to epoxy groups and/or 0.001 to 2 parts byweight of (e) an accelerating agent for the curing reaction of epoxygroups per 100 parts by weight of said (a) and (b).
 7. The heat-fusioncomposition for molding into multi-layers according to claim 6, wherein(d) the polyfunctional compound is a polyfunctional compound containingat least two identical or different functional groups, selected from thegroup consisting of an amino group, carboxylic acid anhydride group,phenolic hydroxyl group, hydroxyl group and carboxyl group, in themolecule.
 8. The heat-fusion composition for molding into multi-layersaccording to claim 6, wherein (e) the accelerating agent for the curingreaction of epoxy groups is at least one kind of compound selected fromthe group consisting of tertiary amines, quaternary amine salts,imidazoles, phosphonium salts and organometallic complexes.
 9. Aheat-fusion composition for molding into multi-layers comprising 20 to80% by weight of a block copolymer having epoxy groups (a), which is anepoxidized block copolymer obtained by epoxidizing a block copolymercomprising a polymer block mainly composed of a vinyl aromatichydrocarbon compound and a polymer block mainly composed of a conjugateddiene compound, wherein the epoxidation is effected by peroxidation ofthe ethylenic double bonds and the epoxy equivalent of the epoxidizedblock copolymer is 140 to 10,000, and 80 to 20% by weight of at leastone kind of thermoplastic elastomer (b) selected from the groupconsisting of styrene elastomers, polyurethane elastomers, polyesterelastomers, polyamide elastomers, polyolefin elastomers and polyvinylchloride elastomers, the combined content of (a) and (b) being 100% byweight and said composition further comprising 10 to 50 parts by weightof (c) at least one kind of hard resin selected from the groupconsisting of an ABS resin, impact resistant polystyrene, polycarbonate,polymethacrylate, polypropylene, saturated polyester resin, polyamide,polyvinyl chloride and polyphenylene oxide resin, 0.01 to 25 parts byweight of (d) a polyfunctional compound containing at least twofunctional groups reactive to epoxy groups and/or 0.001 to 2 parts byweight of (e) an accelerating agent for the curing reaction of epoxygroups per 100 parts by weight of said (a) and (b).
 10. A multi-layermolded body composed of a layer comprising a heat-fusion composition andanother layer, wherein said heat-fusion composition comprises 20 to 80%by weight of a block copolymer having epoxy groups (a), which is anepoxidized block copolymer obtained by epoxidizing (i) a block copolymercomprising a polymer block mainly composed of a vinyl aromatichydrocarbon compound and a polymer block mainly composed of a conjugateddiene compound, or (ii) the hydrogenated product of said blockcopolymer, wherein the epoxidation is effected by peroxidation of theethylenic double bonds and the epoxy equivalent of the epoxidized blockcopolymer is 140 to 10,000, and 80% to 20% by weight of at least onekind of thermoplastic elastomer (b) selected from the group consistingof styrene elastomers, polyurethane elastomers, polyester elastomers,polyamide elastomers, polyolefin elastomers and polyvinyl chlorideelastomers, the combined content of (a) and (b) being 100% by weight.11. The multi-layer molded body according to claim 10, wherein saidanother layer is composed of at least one kind of hard resin selectedfrom the group consisting of an ABS resin, impact resistant polystyrene,polycarbonate, polymethylmethacrylate, polypropylene, saturatedpolyester resin, polyamide, polyvinyl chloride and polyphenylene oxideresin.
 12. The multi-layer molded body according to claim 11, wherein0.01 to 25 parts by weight of (d) the polyfunctional compound containingat least two functional groups reactive to the epoxy group and/or 0.001to 2 parts by weight of (e) the accelerating agent for the curingreaction of epoxy groups are blended with 100 parts by weight of thehard resin of said another layer.
 13. The multi-layer molded bodyaccording to claim 12, wherein (d) the polyfunctional compound is apolyfunctional compound containing at least two identical or differentfunctional groups, selected form the group consisting of an amino group,carboxylic acid anhydride group, phenolic hydroxyl group, hydroxyl groupand carboxylic group, in the molecule.
 14. The multi-layer molded bodyaccording to claim 12, wherein (e) the accelerating agent for the curingreaction of epoxy groups is at least one kind of compound selected fromthe group consisting of amines, quaternary amine salts, imidazoles,phosphonium salts and organometallic complexes.
 15. A multi-layer moldedbody composed of a layer comprising heat-fusion composition and anotherlayer, wherein the heat fusion composition comprises 20 to 80% by weightof (a) a block copolymer having epoxy groups, said block copolymerhaving epoxy groups being an epoxidized block copolymer obtained byepoxidizing (i) a block copolymer comprising a polymer block mainlycomposed of a vinyl aromatic hydrocarbon compound and a polymer blockmainly composed of a conjugated diene compound, or (ii) the hydrogenatedproduct of said block copolymer, wherein the epoxidation is effected byperoxidation of the ethylenic double bonds and the epoxy equivalent ofthe epoxidized block copolymer is 140 to 10,000, and 20 to 80% by weightof (b) at least one kind of thermoplastic elastomer selected from thegroup consisting of styrene elastomers, polyurethane elastomers,polyester elastomers, polyamide elastomers, polyolefin elastomers andpolyvinyl chloride elastomers, the combined content of (a) and (b) being100% by weight, and said another layer is composed of at least one kindof hard resin selected from the group consisting of an ABS resin, impactresistant polystyrene, polycarbonate, polymethylmethacrylate,polypropylene, saturated polyester resin, polyamide, polyvinyl chlorideand polyphenylene oxide resin, 0.01 to 25 parts by weight of (d) apolyfunctional compound containing at least two functional groupsreactive to the epoxy group and/or 0.001 to 2 parts by weight of (e) anaccelerating agent for the curing reaction of epoxy groups are blendedwith 100 parts by weight of the hard resin of said another layer,wherein (d) the polyfunctional compound is a polyfunctional compoundcontaining at least two identical or different functional groups,selected from the group consisting of an amino group, carboxylic acidanhydride group, phenolic hydroxyl group, hydroxyl group and carboxylicgroup, in the molecule, and (e) the accelerating agent for the curingreaction of epoxy groups is at least one kind of compound selected fromthe group consisting of amines, quaternary amine salts, imidazoles,phosphonium salts and organometallic complexes.
 16. A multi-layer moldedbody composed of a layer comprising heat-fusion composition and anotherlayer, wherein the heat fusion composition comprises 20 to 80% by weightof (a) a block copolymer having epoxy groups, said block copolymerhaving epoxy groups being an epoxidized block copolymer obtained byepoxidizing a block copolymer comprising a polymer block mainly composedof a vinyl aromatic hydrocarbon compound and a polymer block mainlycomposed of a conjugated diene compound wherein the epoxidation iseffected by peroxidation of the ethylenic double bonds and the epoxyequivalent of the epoxidized copolymer is 140 to 10,000, and 20 to 80%by weight of (b) at least one kind of thermoplastic elastomer selectedfrom the group consisting of styrene elastomers, polyurethaneelastomers, polyester elastomers, polyamide elastomers, polyolefinelastomers and polyvinyl chloride elastomers, the combined content of(a) and (b) being 100% by weight, and said another layer is composed ofat least one kind of hard resin selected from the group consisting of anABS resin, impact resistant polystyrene, polycarbonate,polymethylmethacrylate, polypropylene, saturated polyester resin,polyamide, polyvinyl chloride and polyphenylene oxide resin, 0.01 to 25parts by weight of (d) a polyfunctional compound containing at least twofunctional groups reactive to the epoxy group and/or 0.001 to 2 parts byweight of (e) an accelerating agent for the curing reaction of epoxygroups are blended with 100 parts by weight of the hard resin of saidanother layer, wherein (d) the polyfunctional compound is apolyfunctional compound containing at least two identical or differentfunctional groups, selected from the group consisting of an amino group,carboxylic acid anhydride group, phenolic hydroxyl group, hydroxyl groupand carboxylic group, in the molecule, and (e) the accelerating agentfor the curing reaction of epoxy groups is at least one kind of compoundselected from the group consisting of amines, quaternary amine salts,imidazoles, phosphonium salts and organometallic complexes.